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31.
C Marchal Escalona J Caballero Alcántara M Padilla León E Villar Alvarez J Villalobos 《Canadian Metallurgical Quarterly》1997,21(9):926-930
Primary prostatic carcinoma accounts for 2% to 4.5% of all neoplasias to this organ, and it has been observed in 2.8% of all radical cystoprostatectomies performed in the Mayo clinic. It originates in the poorly differentiated reservoir cells of the prostatic periurethral ductus which explains why diagnosis is most often obtained in advanced stages (stromal involvement), thus limiting its management to radical surgery. This paper contributes one case report of a patient diagnosed by transrectal biopsy of a primary prostatic transitional carcinoma presenting with incoercible rectorrahges and urinary obstruction symptoms. Treatment was through pelvic exenteration, and urinary and gut by-pass. 相似文献
32.
S. Malato Rodríguez J. Blanco Glvez M. I. Maldonado Rubio P. Fernndez Ibez D. Alarcn Padilla M. Collares Pereira J. Farinha Mendes J. Correia de Oliveira 《Solar Energy》2004,77(5):513-524
This paper briefly describes the different collectors used in solar photocatalysis for wastewater treatment and, based on prior experience, the main advantages and disadvantages of each. As the tubular-shape reactor configuration is the most appropriate for handling and pumping water, the compound parabolic collector (CPC) is proposed as an interesting combination of parabolic concentrators and flat static systems and constitutes a good option for solar photochemical applications. The design of compound parabolic concentrators for solar photocatalytic applications is described in detail and 25–50 mm is proposed as the optimum photoreactor diameter, based on the optical characteristics and optimum concentration of the two photocatalytic systems (TiO2 and photo-Fenton) that can be used with sunlight for wastewater treatment. It has been demonstrated that since aluminium is the only metal that is highly reflective in the ultraviolet spectrum of solar radiation, aluminium-based mirrors are the best option. But, especially when exposed to outdoor conditions, aluminium must be protected and, therefore, at the present time, anodised and electropolished aluminium surfaces are considered the most suitable solutions. As the photochemical reactor contain the working fluid, including the catalyst, it must transmit UV sunlight efficiently and be able to work under enough pressure to handle the high volumes resulting from the large number of collectors in an industrial treatment plant, only low-iron glass is proposed as feasible for constructing the photoreactor (collector absorbers). Finally, ray-tracing algorithm simulations are presented as a design tool for the optical configuration of a particular reactor, drawing conclusions for its improvement and assisting in final engineering decision-making. 相似文献
33.
Milene N.O. Moritz Alyssa R. Merkel Ean G. Feldman Heloisa S. Selistre-de-Araujo Julie A. Rhoades 《International journal of molecular sciences》2021,22(13)
Integrins participate in the pathogenesis and progression of tumors at many stages during the metastatic cascade. However, current evidence for the role of integrins in breast cancer progression is contradictory and seems to be dependent on tumor stage, differentiation status, and microenvironmental influences. While some studies suggest that loss of α2β1 enhances cancer metastasis, other studies suggest that this integrin is pro-tumorigenic. However, few studies have looked at α2β1 in the context of bone metastasis. In this study, we aimed to understand the role of α2β1 integrin in breast cancer metastasis to bone. To address this, we utilized in vivo models of breast cancer metastasis to bone using MDA-MB-231 cells transfected with an α2 expression plasmid (MDA-OEα2). MDA cells overexpressing the α2 integrin subunit had increased primary tumor growth and dissemination to bone but had no change in tumor establishment and bone destruction. Further in vitro analysis revealed that tumors in the bone have decreased α2β1 expression and increased osteolytic signaling compared to primary tumors. Taken together, these data suggest an inverse correlation between α2β1 expression and bone-metastatic potential. Inhibiting α2β1 expression may be beneficial to limit the expansion of primary tumors but could be harmful once tumors have established in bone. 相似文献
34.
In this paper we analyze the determination of “key” sectors in the final energy consumption. We approach this issue from an input–output perspective and we design a methodology based on the elasticities of the demands of final energy consumption. As an exercise, we apply the proposed methodology to the Spanish economy. The analysis allows us to indicate the greater or lesser relevance of the different sectors in the consumption of final energy, pointing out which sectors deserve greater attention in the Spanish case and showing the implications for energy policy. 相似文献
35.
Francisco Jos Alguacil Jos Francisco Muoz Manuel Alonso Aurora Gomez Coedo Maria Teresa Dorado Isabel Padilla 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(5):529-533
ACORGA M5640 (hydroxy‐oxime derivative) has been applied as an extraction reagent for vanadium(V) from sulfate media. The extraction system was studied as a function of contact time, temperature, aqueous pH, diluent of the organic phase, and metal and extractant concentrations. The extraction reaction is endothermic and it is dependent on the organic diluent, aqueous pH and extractant concentration. The data have been analysed numerically to determine the stoichiometry of extracted species and their equilibrium constants. It was found that vanadium was extracted into the organic phase by a complex mechanism which involves the formation of two species (VO2R and VO2R. HR, where R represents the extractant). Vanadium stripping by acidic and ammonium hydroxide solutions was also studied. Copyright © 2003 Society of Chemical Industry 相似文献
36.
FJ Gómez-Pérez VE Valles-Sanchez JC López-Alvarenga R Choza-Romero JJ Ibarra Pascuali R González Orellana OB Pérez Ortiz EG Rodríguez Padilla CA Aguilar Salinas JA Rull 《Canadian Metallurgical Quarterly》1996,48(6):421-424
OBJECTIVE: To examine the effects of vitamin E on total serum protein glycation (fructosamine), hemoglobin glycation (HbA1c), and serum levels of glucose, total cholesterol, triglycerides, LDL-C, HDL-C, apolipoprotein A1 and apolipoprotein B. MATERIAL AND METHODS: Sixty poorly controlled diabetic patients were randomly assigned to receive either 1200 mg/day of vitamin E or identical placebo capsules during a two month period following a double blind cross-over design with a four week wash-out period between regimens. RESULTS: Seven patients were excluded from the study because of reasons not related to the medication. In the remaining 53 patients, the levels of serum glucose, fructosamine, HbA1c, total cholesterol, HDL-C, LDL-C, Apo A1 and Apo B did not vary significantly with vitamin E as compared with placebo. CONCLUSIONS: No significant effects of vitamin E on any of the parameters evaluated were observed in poorly controlled diabetic patients. 相似文献
37.
An estimation-detection scheme is proposed for the estimation of signals with unknown parameters. The scheme is illustrated by considering the case of a signal with unknown but bounded variance. Two sets of bounds are used to determine two regions of signal uncertainty, and different linear estimators are used for each region. A detector is then used to select the appropriate estimator. Since no a priori information is assumed on the unknown parameters a weighted minimax criterion is used to optimize the detector and the estimators. 相似文献
38.
J Calvo JM Vildà L Places M Simarro O Padilla D Andreu KS Campbell C Aussel F Lozano 《Canadian Metallurgical Quarterly》1998,161(11):6022-6029
CD5 is a lymphocyte surface glycoprotein with a long cytoplasmic domain suitable for phosphorylation and signal transduction, which is involved in the modulation of Ag-specific receptor-mediated activation and differentiation signals. In this study, we use Jurkat T cell transfectants of CD5 cytoplasmic tail mutants to reveal phosphorylation sites relevant to signal transduction. Our results show that casein kinase II (CKII) is responsible for the constitutive phosphorylation of CD5 molecules at a cluster of three serine residues located at the extreme C terminus (S458, S459, and S461). Furthermore, the yeast two-hybrid system demonstrates the specific association between the C-terminal regions of the CD5 cytoplasmic tail and the regulatory beta subunit of CKII. We demonstrate that CKII associates with and phosphorylates the C-terminal region of CD5, a conserved domain known to be relevant for the generation of second lipid messengers, and thereby enables at least one component of its signaling function. 相似文献
39.
40.
Analysis of intrachip electrical and optical fanout 总被引:1,自引:0,他引:1
We examine the benefits of electrical isolation in intrachip optical signaling. We calculate the delay and energy metrics of an optical interconnect with fanout driving an electrical load. By examining fanout and including load drivers into delay equations, we make a shift from the general trend of looking at optical interconnects as a replacement for long parasitic wires. Our calculations show that optical fanout provides a large improvement in an Etau2 (energy delay squared) metric and improves performance even at very short intrachip distances. The break-even length corresponds to the wiring length of 250 minimum-size inverters that are compactly laid out. These results provide a compelling reason to further examine the implementation of optical interconnects. 相似文献